Momo95, you can't really "safely say" anything about the take home pay, but £25k doesn't seem likely to be an accurate figure. What's really worth noting about the £12k bond repayment is that it's not taxed. As such, repaying a similar loan amount (assuming that's how the training was funded) would require a substantially higher pay with another employer to achieve the same take home pay, considering you'd be repaying it out of income which had already been taxed (which is what G-FORC3 was getting at). You're also only correct about the £12k going straight to the bank for those who are repaying a loan. For any cadets who managed to fund it independently (through savings or family or whatever) they'd still receive the £12k on top of their salary. Anyway, the figures are all there to interpret as you wish.
NathanJohnston, best of luck next year.